Decreasing charge time of FLA house bank

[haveaday]

Hello,

I have a FLA house bank made up of 8 GC2 batteries. This is a 12v house bank with each battery providing 215ah. So, wired in series and parallel it's a 12v, 860ah bank. Overnight running refrigeration and a few other house loads the bank is usually discharged 230-300ah by the morning. I then fire up the generator and at first the charge rate into the batteries is about 40amps from my 2600w inverter / charger rated for 120amps of charging. If I start the main engine and allow the 12v alternator on it (100amps and dedicated to charging the house bank) to also charge I can increase the charge rate to 60-70 amps. So, my question is... is there something wrong with my inverter? Is there a way to increase the charge rate without running a 12 liter diesel for the purpose of producing about 25amps of 12v?

The inverter is a Charles industries IQC-2600 original to the 2003 boat.

Thanks
Ben

[four winds]

The manual for your charger states there is a programming switch with four settings. 8,16,32,64 amps.

Google, iqc-2600 Charles

And you can find a link to a pdf manual.

[GordMay]

Greetings and welcome aboard the CF, Ben.

IQC Manual ➥ http://www.vanner.com/manuals/IQ12-2600.pdf

[four winds]

You can find the manual here.

Product Manuals

I notice you said it's a 120 amp charger. So thought my last post must be in error.

Went back to the manual and notice it says to set multiplies of the switches to combine amps for desired charge rate.

Seems you need to set all four switches "on" to get the max output.

Seems Charles is Vanner brand, BTW.

Hope this helps.

[haveaday]

Sorry, I should have said that I did start with RTFM. I checked the dip switches last night and made sure all four are on. Additionally, I verified the switch is in the FLA mode.

Thanks
Ben

[Cheechako]

If you are using 230-300 Ah overnite.... WOW! Do you have a machine shop on board running graveyard shift? :>)

[haveaday]

Originally Posted by Cheechako

If you are using 230-300 Ah overnite.... WOW! Do you have a machine shop on board running graveyard shift? :>)

No, but I do have four fridges / freezers on board. 1 is a small marine fridge while the other 3 are undercabinet household run off the inverter. Two are about a year old but the freezer is original to the boat, made in 2002. I am somewhat suspicious that it is the main culprit killing the batteries. It looks to me like when it is fully running it can draw about 20 amps of 12v, which would correspond to about 240w or 2a of 120.

Ben

[four winds]

Originally Posted by haveaday

Sorry, I should have said that I did start with RTFM. I checked the dip switches last night and made sure all four are on. Additionally, I verified the switch is in the FLA mode.

Thanks

Ben

Cool. Good on ya.

Maybe the troubleshooting section has an entry for low charge output? Maybe a reset proceedure? Since there is likely some "code" in there somewhere.

[Dave Lochner]

Originally Posted by haveaday

No, but I do have four fridges / freezers on board. 1 is a small marine fridge while the other 3 are undercabinet household run off the inverter. Two are about a year old but the freezer is original to the boat, made in 2002. I am somewhat suspicious that it is the main culprit killing the batteries. It looks to me like when it is fully running it can draw about 20 amps of 12v, which would correspond to about 240w or 2a of 120.

Ben

Running high load AC appliances off of 12v wastes a lot of energy. The first solution to your issue is to reduce energy consumption by using shore power or get 12v appliances.

As the charge state of the battery bank increases, the acceptance rate of the batteries decreases. More energy is lost due to heat and and separating hydrogen atoms from oxygen atoms than recharging the plates. When deeply discharged the charger may initially put 100 amps in, as it approaches 80% state of charge, the amount will be much lower.

Look around for articles by Maine Sail on this and other forums, he goes into great detail about these issues.

[rom]

Originally Posted by haveaday

Hello,

I have a FLA house bank made up of 8 GC2 batteries. This is a 12v house bank with each battery providing 215ah. So, wired in series and parallel it's a 12v, 860ah bank. Overnight running refrigeration and a few other house loads the bank is usually discharged 230-300ah by the morning. I then fire up the generator and at first the charge rate into the batteries is about 40amps from my 2600w inverter / charger rated for 120amps of charging. If I start the main engine and allow the 12v alternator on it (100amps and dedicated to charging the house bank) to also charge I can increase the charge rate to 60-70 amps. So, my question is... is there something wrong with my inverter? Is there a way to increase the charge rate without running a 12 liter diesel for the purpose of producing about 25amps of 12v?

The inverter is a Charles industries IQC-2600 original to the 2003 boat.

Thanks
Ben

What happens when you're at the dock ? Can your battery absorb 120A ? Your alt does not run through the inverter and should put close to 100A in your batt alone. Your inverter should be able to do the same on his own. But what's strange is that running them together increases amps, meaning that your batts are willing to get some more ...
So its more like both your alt & generator are not runnning at their rated power.

[john61ct]

Have you physically checked actual input voltages during the three scenarios, A vs B vs A+B?

An even slight increase in voltage may be "pushing" higher amps?

[haveaday]

Originally Posted by john61ct

Have you physically checked actual input voltages during the three scenarios, A vs B vs A+B?

An even slight increase in voltage may be "pushing" higher amps?

I have not, but that's a great idea and makes sense. I'll check that next opportunity I get.

[haveaday]

Originally Posted by rom

What happens when you're at the dock ? Can your battery absorb 120A ? Your alt does not run through the inverter and should put close to 100A in your batt alone. Your inverter should be able to do the same on his own. But what's strange is that running them together increases amps, meaning that your batts are willing to get some more ...
So its more like both your alt & generator are not runnning at their rated power.

I don't think I've seen 120a under any circumstance but I now think I'm not sure enough about that. Next time I get to shore power I will watch that much more carefully.

Here's another interesting thing I've noticed. At times when the Air Conditioner kicks in and I can hear the generator work hard the amperage going into the batteries also increases. I'm not sure if the generator going closer to full field also causes it to increase voltage. I had to replace the voltage regulator on the generator about a year ago. It is working fine by all accounts but this might be a data point that points to some need for adjustment. I'll also call Charles or Vanner tomorrow and see if they have any ideas. I fear that with the age of the equipment and Charles' exit from most of the marine business they might simply suggest replacement. If there's actually something wrong with the inverter I'd be happy to go to a Victron or something more modern but not just for grins.


Ben

[haveaday]

Originally Posted by Dave Lochner

Running high load AC appliances off of 12v wastes a lot of energy. The first solution to your issue is to reduce energy consumption by using shore power or get 12v appliances.

As the charge state of the battery bank increases, the acceptance rate of the batteries decreases. More energy is lost due to heat and and separating hydrogen atoms from oxygen atoms than recharging the plates. When deeply discharged the charger may initially put 100 amps in, as it approaches 80% state of charge, the amount will be much lower.

Look around for articles by Maine Sail on this and other forums, he goes into great detail about these issues.

The boat involved is a Carver Voyager 570. I have many datapoints that suggest Carver didn't intend the boat to be used as a true cruising boat the way we are using it. The cost of replacing all the household fridges with proper 12v marine fridges is likely not worth it. We've seen too many other limitations for this boat in a cruising role and will likely look to move to something better suited for the kind of cruising we're doing with it. We're from Chicago and have boated on the great lakes our entire boating careers. We're currently in the Bahamas with the boat and seeing some limitations. A the same time the boat has gotten us here and gives great living space for my wife, two daughters and me.

Ben

[skipgundlach]

FLA tech is older than even I am - but still a mystery.

I just went through a very deep change - new cabling for anything which touched the house (4x L16H-AC, net 870AH) or starter battery, and new Trojans.

My charging behavior changed notably. I also followed Rod Collins (MaineSails) advice and made all of my interconnects the exact same length, and followed Trojan's wiring diagram as to how to do the incoming/outgoing master +/- cables. I also heeded his dissatisfaction with my previous layout which included one + cable overlapping one - cable; they are all led fair, and even the various monitor connections do not have any crossings in them. YMMV but it seems to have helped...

It's not entirely perfect, but now all the individual batteries are within a degree or so of each other, and don't get very warm despite being charged at the most the dock can provide (on the dock during this exercise, which included trying to save the first set), and the in/out cables, and the parallel cables between the two +/- terminals are all within an amp of each other; it has meant that my demonstrated inrush of current has gone up by 10% without any other change on my part.

You may have done all that already, of course. Have you metered the amps coming through the cables involved (verifying that you're getting all the amps to the battery you are 'paying for')? I kept doing that until I got a consistent reading. I also went back and retorqued all the settings of all the bolts where connections were made; all were new lugs, so I was confident in those, but felt that I could perhaps improve if I used a torque wrench instead of my hand strength. Sure enough, there were some which moved...

Your amp hour drop overnight, however, will be difficult to recapture in the length of time you have available - unless you are on shore power or constant generator power. Even I, with my wind and solar (now upgrading to 720W) assisting, expect to have to run my Honda 2000 feeding my (nominal) 70A charger, for some time, as our overnight usage is in the 70-100AH (depending on heat; the reefer/freezer is the culprit for us as well) range.

Our previous set (and likely the one before that) was, from all the pros' analysis, killed by chronic undercharging; it was exacerbated by cabling and other issues. We have bought (through MaineSails) a Balmar Smartgauge to supplement our amp counters; we regularly quit charging early, apparently, but won't make that mistake again.

Because...

Look at the data as to how much amperage, at what period of time, needs to be put back into a FLA bank. It astounded me; you may already know it, but it's distressing to think of how long it takes to recapture those amps unless you have some form of constant input, and, particularly, how long it takes to float off that much of a bank.

I'll be interested to see how you get on, as my inverter charger, subject of a different thread, while it wasn't as bad as yours, was doing the same sort of thing - delivering too few amps despite the readout in the display. I've lessened that discrepancy, but the rest of it likely is its 10 year age.

L8R

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